Achieving significant reductions in tobacco use by children and youth is one of the most important challenges in cancer prevention today. There is a pressing need to develop and evaluate innovative strategies that stimulate youth involvement, link prevention programs with today's dynamic tobacco control policy environment, and are effective in multiethnic populations. The aims of this study are to: 1) Evaluate the impact of a school-based smoking prevention intervention that emphasizes active involvement of middle school students, on rates of regular smoking and smoking initiation in a multiethnic cohort of youth in Hawaii; 2) investigate cultural factors associated with tobacco use among Japanese, Chinese, Filipino, Native Hawaiian, and Caucasian youth; and 3) determine the relationships among access to tobacco products, youth smoking rates, and sources of tobacco among youth in Hawaii. We will conduct a randomized trial of a Student Involvement Intervention (SII) with its foundations in a conceptual framework that blends Social Cognitive Theory, Social Action Theory and the Sense of Coherence construct from Antonovsky's salutogenic model of health behavior. Twenty middle schools in Hawaii will be randomly assigned to the SII or a Standard Prevention Program (SPP). The SII has three main components: Virtual Tobacco-Free Classroom, Youth Drama Education, and Youth Advocacy Training. The 2 year intervention will be evaluated prospectively in a cohort of 7th graders, with surveys at baseline, one year, and two years. The main outcome will be mean 30 day smoking prevalence rates in each school. The final outcome will also be measured with biochemical assessments using saliva continine in a sub-sample of schools in both study arms. Cultural influences will be examined using both quantitative and qualitative methods. Access-use associations will be assessed by ecological analyses comparing individuals' reports with compliance check findings. The proposed study fills important research gaps concerning young people's smoking. It leads a new generation of prevention trials by testing innovative, creative, relevant strategies while increasing our understanding of cultural influences on youth smoking and of the impact of tobacco control policies.